The document discusses several deep learning frameworks including TensorFlow, Keras, PyTorch, Theano, Deep Learning 4 Java, Caffe, Chainer, and Microsoft CNTK. TensorFlow was developed by Google Brain Team and uses dataflow graphs to process data. Keras is a high-level neural network API that runs on top of TensorFlow, Theano, and CNTK. PyTorch was designed for flexibility and speed using CUDA and C++ libraries. Theano defines and evaluates mathematical expressions involving multi-dimensional arrays efficiently in Python. Deep Learning 4 Java integrates with Hadoop and Apache Spark to bring AI to business environments. Caffe focuses on image detection and classification using C++ and Python. Chainer was developed in collaboration with several companies